Your Digest for Wednesday, Feb 07, 2024 12:59 PM


UpperLimbNeurologyPoster.png
| Klumpke's paralysis | Erb's palsy |
| ------------------------------------------------------------------------------------ | ----------- |
| C8 / T1 lesion | |
| Claw hand due to unopposed action of long flexors and extensors | |
| Can have associated Horner's Xn (C8,T1 are in close proximity to sympathetic chain). | |
| Damage to one can cause damage to the other. | |
| Seen in breech delivery. (upward traction on arm) | |
| Loss of function of lubricals and wrist flexors | |
| Lumbricals flex the MCP joints and extend the PIP and DIP joints; | |
| In KP, there is | |


Causes of diabetes insipidus

Central Nephrogenic
Intracranial SOL / pituitary surgery / trauma etc Lithium
Infiltrative diseases: Histiocytosis, Sarcoidosis, (but ?not amy_loidosis) ⬆Ca, ⬇K
Haemochromatosis Demecloclycline
DIDMOAD (ada Wolfram Syndrome) Inherited:
Common- ADH receptor mutation
Rare: aquaporin 2 mutation
posteriorPituitaryInfiltrationDiabetesInsipidus.png

[!INFO] Relevant cerebral lobes
Mnemonic: PITS ->

opticRadiationsVisualpathway.png

visualFields.png

Characteristic EDH-epidural/ extradural SDH-subdural
Patient Young, Hx of trauma Old
Aetiology Usually trauma, spontaneous is very rare Commonest is traumatic, cerebral atrophy (old age, chronic alcohol use) is a major risk factor
- Tamponade effect will control rate of bleeding (as it’s venous)
Type of bleed 80% arterial, therefore rapid Mostly venous / small arteries
Site Commonly middle meningeal artery at [[foramen spinosum.png]] Bridging vein or other sites
Plane Potential space between dura and skull Between dura and arachnoid
Presentation Lucid interval → rapid decrease Can be acute or chronic.
Imaging Lens shaped, does not cross suture lines, crosses dural attachments Crescent shaped, crosses suture lines, does not cross dural attachments
- Chronic changes occur: Encapsulation and resorption / hygroma formation
Also seen in trauma most common type seen in trauma
Lower impact, lucid interval present Caused by Higher energy impacts - patient won't regain consciousness
brief, linear contact force to the skull. Can Occur in less severe trauma (antigoagulants, old age are RF)
Arterial or venous. (commonest site = middle meningeal artery);
caused by disruption of vessels secondary to dura separating from skull.
Mechanism: tearing of veins due to relative movement of brain due to acceleration
rare in age > 60 as 'dura is tightly adherent to the skull' highest incidence in 40s to 70s.
most are acute. Can be acute or chronic
extraduralHaematoma.png subduralhaematoma.png
Source

OR
Wernicke = Word Salad. (W - W)

Wernicke's Brocas Conduction aphasia Global aphasia
Receptive Expressive
Fluent Non fluent
"Word salad" "Tip of the tongue" Speech fluent; repetition poor;
comprehension preserved.
All of the above;
can communicate with guestures
Superior temporal gyrus Inferior frontal gyrus Arcuate fasciculus All regions affected
Middle Cerebral artery Middle cerebral artery

[!TIP] Mnemonic: The parietal lobe is responsible for interpretation of "things in space";
Symbols lose meaning - agraphia, acalculia, alexia,
Disorientation
Spatial structure of tactile stimuli is lost - "cortical sensory loss"
Astereognosis

  1. simultagnosis (inability to identify things in context - i.e can see trees but can't recognize Forrest)
  2. Hemispatial neglect

Temporal lobe dysfunction

temporalLobe.png
LimbicSystemAndHippocampus.png

[!TIP] Mnemonic:
The temporal lobe seems to be involved in

  1. processing and interpretation of sensory stimuli
  2. predominantly auditory, also visual, smell etc.
  3. Emotional regulation
  4. Memory

Functions:

  1. Processing sensory stimuli - Mainly sound ( but also vision, smell etc)
  2. Memory - Hippocampus. (hippocampus is involved in making long term, emotionally connected memories)
  3. Language comprehension
  4. Understanding social cues
  5. Facial recognition
  6. Emotional regulation -> possibly due to involvement of the amygdala which is located in the medial temporal lobe.
    1. fear is a predominant emotion seen in temporal lobe problems.
  7. Attention
  8. Reward processing and motivation.

Features of temporal lobe dysfunction:

Function Dysfunction
facial recognition prosopagnosia - inability to identify faces
Language comprehension Wernicke aphasia
Processing visual stimuli Visual agnosia
Processing sound Sensoryneural hearing loss, word deafness, difficulty in interpreting sounds
Attention problems paying attention amidst other stimuli <-? difficulty in filtering out sensory stimuli?
Disrupted sensory processing during TLE Temporal lobe epilepsy: not significant motor component as TL isn't involved in motor function.
Features include déjà vu, unprovoked fear, visual distortions, and strange tastes and smells.
Memory Inability to form new long term memories or if severe, loss of previous long term memories associated with self identity ->
which can lead to personality change
Source

Causes of QT prolongation:

Congenital Drugs Other
- Jervell-Lange-Nielsen syndrome (includes deafness and is due to an abnormal potassium channel)
- Romano-Ward syndrome (no deafness)
- amiodarone, sotalol, class 1a antiarrhythmic drugs
- tricyclic antidepressants, fluoxetine
- chloroquine
- terfenadine
- erythromycin
- electrolyte: hypocalcaemia, hypokalaemia, hypomagnesaemia
- acute myocardial infarction
- myocarditis
- hypothermia
- subarachnoid haemorrhage
  1. Amiodarone is the drug of choice for for treatment of haemodynamically unstable VT.
  2. Verapamil should never be used in VT - ?why
    F

The classic description of the left cardiac ventricle is as containing two papillary muscles: the anterolateral and posteromedial.[2] The anterolateral arises from the sternocostal wall, and the posteromedial papillary muscle arises from the diaphragmatic wall of the ventricle. The right ventricle contains three papillary muscles, classically described as anterior, posterior, and septal. Source

Left anterolateral papillary muscles derives from branches of the left coronary artery. The blood supply to the left posteromedial papillary muscles most commonly derives from the right coronary artery Source
papillaryMuscles.png


[!INFO] Azithromycin
used as last resort add on therapy
Reduces exacerbation frequency but promotes antibiotic resistance.


Pulmonary arterial hypertension

Pathologic findings in pulmonary arterial hypertension:

Treatment:
Two groups: